Circuit for the control of a winch by fluid under pressure including an unwinding position

ABSTRACT

The invention refers to a circuit for the control of a winch by fluid under pressure including an unwinding position. The circuit includes a first calibrated valve arranged in the delivery pipe from the motor of the winch, whilst a second calibrated valve is likewise arranged in the pipe downstream of the valve with respect to the motor, and a tie-pipe connects the pipe between the valves to the feedpipe to the motor, a constriction being arranged in this pipe. A circuit of this kind is applicable to the control of the winch motor of a trawl.

United States Patent Pinson July 22, 1975 [54] CIRCUIT FOR THE CONTROL OF A WINCH 3,300,969 1/1967 Barden 91/418 X FLUID UNDER PRESSURE INCLUDING 3,360,304 12/1967 Adams et al. 91/462 X AN UNWINDING POSITION Primary Examiner-Edgar W. Geoghegan [75] Inventor: Claude M. Pinson, Senlis, France Attorney, Agent, or Firm-Mason, Fenwlck & [73] Assignee: Societe Anonyme: Poclain, Le Plessis Lawrence Belleville, France 1 7 [22] Filed May 3, 19 4 ABSTRACT [21] Appl. No.: 469,687

The invention refers to a circuit for the control of a winch by fluid under pressure including an unwinding [30] Apphcatmn Pnonty Data position. The circuit includes a first calibrated valve May 25, 1973 France 73.19210 arranged in the delivery pipe from the motor of the winch, whilst a second calibrated valve is likewise arranged in the pipe downstream of the valve with re- 60/905 spect to the motor, and a tie-pipe connects the pipe [51] Int. Cl. ..F15B 11/08; F15B 13/04 between the-valves to the feedpipe to the motor, a Field of Search 0/ constriction being arranged in this pipe. A circuit of this kind is applicable to the control of the winch [56] References Cited motor of a trawl.

UNITED STATES PATENTS 4 Cl 3 D 2,082,473 6/1937 Tyler 60/905 x rawmg F'gures SHEET 5 R NM fin NN WNW QN @N w? m m? PATENTED JUL 2 2 I975 l lu PATENTED JUL 2 2 ms SHEET bm r M 9% \T Q a L" m MW NM Mm N w WM Q 7 J AU lllL l(\ Ill .N/; .r W TV n J- K 4 MN ii @w W BN m w Q W V! y Ir .IL Ply 4 1 B w ml & N Qui CIRCUIT FOR THE CONTROL OF A WINCH BY FLUID UNDER PRESSURE INCLUDING AN UNWINDING POSITION In the domain of trawling the net is more and more manipulated by means of a winch coupled to a motor operated by fluid under pressure, generally hydraulic.

The various control circuits which have been proposed hitherto pay out the net poorly, corresponding with undwinding of the winch. It is in fact necessary as a function of multiple parameters such as the portion of the net already put into the water, which is varying all the time, the position of the boat with respect to the swell, etc., to ensure a certain retaining force on the net which varies in a complex manner.

The invention proposes a new circuit suitable for effecting the required paying out but the application of which is not of course limited solely to the control of the unwinding of a trawl winch.

The object of the invention is therefore a circuit for the control of a winch by fluid under pressure including an unwinding position, consisting of:

a fluid motor having an inlet chamber and an exhaust chamber for the fluid,

a source of fluid under pressure,

a fluid tank,

a feed-pipe connecting the source of fluid to the inlet chamber,

a delivery pipe connecting the exhaust chamber to the tank,

a first calibrated valve which is arranged in the delivery pipe,

a tie-pipe which is connected on the one hand to the delivery pipe downstream of the first calibrated valve with respect to the motor and on the other hand to the feed pipe, and

a member for adjustment of the flow of fluid, arranged in the tie-pipe.

A second calibrated discharge valve is arranged in the delivery pipe downstream of the connection of the tie-pipe to this delivery pipe with respect to the first calibrated discharge valve, the member for adjustment of the flow consisting of a constriction.

Preferably the circuit further includes:

a pipe by-passing the first and second calibrated valves, which is connected to the delivery pipe on the one hand between the motor and the first calibrated valve and on the other hand downstream of the second calibrated valve with respect to the first calibrated valve,

a first regulator having at least two positions, which is arranged in the by-pass pipe and which in its first position blocks at its level the by-pass pipe and in its second position ensures at its level the continuity of the said by-pass pipe,

a second regulator having at least two positions, which is arranged in the tie-pipe and which in its first position ensures at its level the continuity of the tiepipe and in its second position blocks at its level the said tie-pipe,

and a tie ensuring correspondence respectively of the first position of the first regulator with the first position of the second regulator and of the second position of the first regulator with the second position of the second regulator.

Advantageously the tie consists of:

a source of piloting fluid,

a first jack and a first retum-member which are coupled to the movable member of the first regulator, the first jack being connected by a first piloting pipe to the source of piloting fluid and having an effect upon the said movable member, which is opposed to that of the first return-member, this latter effect returning the said movable member towards the second position of the first regulator,

a second jack and a second return-member which are coupled to the movable member of the second regulator, the second jack being connected by a second piloting pipe to the source of piloting fluid and having an effect upon the said movable member, which is opposed to that of the second return-member, this latter effect returning the said movable member towards the second position of the second regulator, whilst the first-and second piloting pipes have a common portionb y means of which they are connected to the source of piloting fluid and that a third regulator having at least two positions is arranged in this common portion, in its first position ensures at its level the continuity of the common portion, and in its second position puts the first and second piloting pipes in communication with the fluid tank.

It is often of interest to provide a third calibrated valve called the non-retum valve and to arrange it in the delivery-pipe downstream of the second calibrated valve and of the connection to the by-pass" pipe, which is itself located downstream of the said second calibrated valve with respect to the first calibrated valve. In this case the source of piloting fluid consists of the portion of the delivery pipe lying between the second and third calibrated valves.

The invention will be better understood and secondary characteristics as well as their advantages will become apparent in the course of the description of an embodiment given below as an example.

It is to be understood that the description and the drawings are given only by way of indication and nonrestrictively.

Reference will be made to the attached drawings, in which:

FIG. 1 displays diagrammatically a circuit in accordance with the invention in a first configuration:

FIG. 2 displays the circuit as shown in FIG. 1 but in the configuration particular to unwinding of the winch; and

FIG. 3 displays the operational graph of the circuit as shown in FIG. 2 during unwinding of the winch.

- Turning to FIG. 1, it will be observed that a pump 1 is connected by its suction pipe 2 to a fluid tank 3 and by a pipe 4 connected to its delivery aperture, to a three-position regulator valve 5 which is provided with a control handle 6.

Furthermore, a motor 7 comprising two chambers 8 and 9 is connected to the regulator valve 5 by two pipes 10 and 11, the pipe 10 being connected to the chamber 8 and the pipe 11 being connected to the chamber 9. A flow limiter l2 intended in a manner in itself known to provide the function of limiter of the speed of the motor 7 is arranged in the pipe 11 so as to allow flow of the fluid from the said motor towards the regulator valve 5. Again in manner known, this flow limiter 12 has its opening piloted by the pressure of the fluid contained in the pipe 10, that is, by means of a pipe 13 connected to the said pipe 10. Finally, a pipe 14 is connected to the pipe 11 on opposite sides of the flow limiter 12, whilst a non-return valve 15 is arranged in the pipe 14 and allows flow of the fluid from the regulator valve 5 towards the motor 7. It may be further observed that the presence of the flow limiter 12 is not indispensable to putting of the invention into effect.

A pipe 16 is tapped off from the pipe 4 which it connects to the tank 3. A calibrated discharge valve 17 is in addition arranged in this pipe 16. A pipe 18 likewise connects the regulator valve 5 to the tank 3. Three calibrated valves 19, 20 and 21 are arranged in succession in the pipe 18 starting from the regulator valve 5. The calibration pressures of these valves are in the case in point, distinct. The calibration pressure of the valve 19, for example, is equal to 150 bars and in the example illustrated is higher than the calibration pressure of the valve 20, which is equal to 100 bars. As to the valve 21 it only has to provide a weak retention. Its calibration pressure is therefore low, being of the order of, for example, bars.

A tie-pipe 22 connects the portion of the pipe 18 lying between the calibrated valves 19 and to the pipe 4. A constriction 23 is arranged in this tie-pipe 22, as well as a two-position regulator valve 24. A return spring 25 and a jack 26 are coupled to the said regulator 24 and have opposing actions, the spring 25 tending to keep the regulator valve 24 in its second position in which it is furthermore represented in FIG. 1. In its first position, the regulator 24 ensures at its level, continuity of the tie-pipe 22, whereas in its second position it blocks at its level the said pipe 22.

A by-pass pipe 27 is connected to the pipe 18, on the one hand between the regulator valve 5 and the first calibrated valve 19 and on the other hand between the second calibrated valve 20 and the third 21. Another two-position regulator valve 28 is arranged in the bypass pipe 27. A return spring 29 and a jack 30 are coupled to the regulator valve 28 and have opposing actions, the spring 29 tending to keep the regulator valve 28 in its second position in which it is furthermore represented in FIG. 1. In its first position the regulator valve 28 blocks at its level the pipe 27 whereas in its second position it ensures at its level, continuity of the said pipe 27.

It is to be observed finally that a third two-position regulator valve 31 furnished with a handle 32 is arranged in a pipe 33 connected to the pipe 18 between the second and third calibrated valves 20, 21. Control jack 30 of regulator 28 is connected to one end of a first piloting pipe 34 which has its opposite end connected to a second piloting pipe 35 and to one end of pipe 33 with the other end of the second piloting pipe being connected to jack 26 of regulator 24. The opposite end of pipe 33 is connected to conduit 18 at a location between calibrated valves 20 and 21. Additionally, pipe 36 provides a flow connection between regulator valve 31 to the tank 3. This regulator valve 31 in its first position ensures continuity at its level, of the pipe 33 and blocks the pipe 36, whereas in its second position (represented in FIG. 1) it interrupts at its level the pipe 33, connecting the portion of this pipe 33 which is connected to the piloting pipes 34 and 35, to the pipe 36.

It is to be observed again that the three positions of the regulator valve 5 correspond:

the first position, with putting into communication the pipes 4 and 10, and 11 and 18;

the second position, represented in FIG. 1, with putting into communication the pipes 4 and 18 and blocking at the level of the regulator valve 5, the pipes 10 and 11;

the third position, with putting into communication the pipes 4 and 11, and 10 and 18.

FIG. 2 illustrates the same circuit as FIG. 1 with the elements referenced with the same numerals. The sole difference rests in the fact that the various regulators 5, 24, 28 and 31 have all been put in their respective first positions. The configuration shown in FIG. 2 being of particular interest it appears advisable at this point to make the following remarks proper to this configuration:

the aggregate of the pipes 4 and 10 constitutes the feed-pipe to the inlet chamber 8 of the motor 7;

the aggregate of the pipes 11 and 18 constitutes the fluid delivery pipe out of the exhaust chamber 9 of the motor 7;

finally, the tie-pipe 22 effectively connects, without being interrupted, the pipes 18 and 4 whereas with the pipe 27 blocked at regulator 28 the fluid from the pipe 11 can only escape through the first calibrated valve 19.

FIG. 3 represents the curves of the variations obtained during operation of the circuit as shown in FIG. 2. As a function of the speed of rotation N of the motor 7 there are represented the variations in the pressure PA of the feed fluid contained in the pipes 4 and 10, and in the pressure PR of retention of the fluid contained in the portion of the pipe 11 lying between the motor 7 and the flow limiter 12.

The operation obtained by putting into effect the device represented in FIG. 2 is explained next.

The pump 1 feeds fluid to the inlet chamber 8 of the motor 7.

When the motor 7 is rotating at low speed, between 0 and N2 r.p.m., for example, the flow from the pump 1 is greater than the flow that the motor 7 can make use of. In this case the excess flow passes towards the tank 3 through the pipe 22, the constriction 23 and the calibrated valves 20 and 21.

When the speed of the motor is very low (less than N1) the load loss created by the constriction 23 is greater than the calibration pressure of the calibrated valve 19. The motor torque is then positive.

When the speed of the motor driven by the trawl net lies between N1 and N2 the flow from the pump 1 is still greater than the flow necessary to feed the inlet chamber 8 of the said motor, but the load loss created by the constriction 23 is less than the calibration pressure of the calibrated valve 19 and the motor torque is negative, which corresponds with braking the motor.

When the speed of the motor driven by the trawl net lies between N2 and N3 the flow from the pump 1 is no longer sufficient to feed the motor. This flow is complemented by the return flow from the motor passing through the constriction 23, the pipe 22 and the regulator 24. The load loss created by the constriction 23 increases with the flow contributed so that the feed pressure falls, increasing all the more the effective retention pressure. Normally, the feed flow increases with increases in speed with flow through pipe 22 also increasing. As a matter of fact, when PR becomes greater than PA, the pressure differential across constriction 23 also increases.

In the limit, beyond N3, between N3 and N4, closure of the speed limiter 12 intervenes quickly though progressively, and brings about a very considerable increase in the pressure PR which causes powerful braking on the motor 7. g

It is to be noted that in the range from 0 to N2 the variations in PA and consequently in PR are modulated progressively. That is due to the fact that when the flow from the pump 1 is greater than the flow necessary to feed the inlet chamber 8, the excess flow returns to the tank 3 through the pipe 22 by passing through the constriction 23 from the pipe 4 towards the pipe 18. With the constriction 23 creating a load loss the pressure in the pipe 4 is greater than the pressure in the portion of the pipe 18 to which is connected the pipe 22. The pressure in the pipe 4 is therefore greater than the calibration pressure of the calibrated valve 20, which leads to the obtaining of the descending curve of variation represented for PA in FIG. 3 in the range from 0 to N1.

On the other hand when the motor 7 is driven by the net at a higher speed (range N2 to N4), the flow from the pump 1 becomes insufficient. A compensating flow in an amount equal the pump deficiency is injected into the pipe 4 through the pipe 22 and the constriction 23. The pressure in the pipe 4 is then equal to the calibration pressure of the valve 20, this time reduced by the value of the load loss introduced by the constriction 23. The pressure PA has a variation in accordance with that represented in FIG. 3 in the range N2 to N4.

The overall result is the obtaining of a curve of the variation of the retention pressure PR in accordance with What is likewise shown in FIG. 3. Now, experience shows that a curve of variation of PR like this is very nearly the curve of variation which would correspond with the characteristics of an ideal holding-back of the trawl in the course of paying out, taking into account the whole of the parameters coming into play in the employment of the trawler carrying the trawl. It is this very satisfactory approach to ideal holding back which is precisely the object of the invention, the essential means combined to do this being the addition to a known control circuit, of the two valves 19 and 20 and the constriction 23.

Naturally, the complete circuit proposed presents certain other equally interesting characteristics such, especially, as that corresponding with the neutralization of the constriction 23. In short, it may be required for certain utilizations not to obtain the modifications of the variations in the pressures PA and PR caused by putting into use the calibrated valves 19 and 20 and the constriction 23. In that case putting the regulator 31 into its second position will put the jacks 26 and 30 in communication with the pressureless fluid contained in the pipe 36 and in the tank 3. The regulators 24 and 28 will in this way be arranged too in their respective second positions (FIG. 1) in which no fluid can pass through the constriction 23, the delivery of the fluid which has passed through the flow limiter 12 being effected through the pipe 27 in which this fluid should pass through the calibrated valves 19 and 20.

The invention is not limited to the description which has just been given but on the contrary covers any variants upon it which might be applied to it without departing from its scope or its spirit.

What we claim is:

l. A hydraulic circuit for the control of a winch by fluid under pressure, including an unwinding position, comprising:

a fluid motor having an inlet chamber and an exhaust chamber for the fluid,

a source of fluid under pressure,

a fluid tank,

a feed-pipe connecting the source of fluid to the inlet chamber, 1

a delivery pipe having an upstream end connected to the exhaust chamber and a downstream end communicating with the fluid tank,

a first calibrated discharge valve which is arranged in the delivery pipe,

a connecting tie-pipe which is connected on one end to the delivery pipe downstream of the first calibrated discharge valve with respect to the motor and is connected on an opposite end to the feed pipe,

a flow constriction member for adjustment of the flow of fluid in the tie-pipe,

and a second calibrated discharge valve arranged in the delivery pipe downstream of the connection of the tie-pipe to the delivery pipe.

2. A circuit as in claim 1, including:

a by-pass pipe by-passing the first and second calibrated valves, which by-pass pipe has one end connected to the delivery pipe at a location between the motor and the first calibrated valve and which has its other end connected to the delivery pipe at a location downstream of the second calibrated valve with respect to the first calibrated valve,

a first regulator valve having at least two positions, which is mounted in the by-pass pipe and which in its first position blocks the by-pass pipe and in its second position ensures the continuity of the said by-pass pipe,

a second regulator valve having at least two positions, which is arranged in the connecting tie-pipe and which in its first position ensures the continuity of the connecting tie-pipe and in its second position blocks the said tie-pipe,

and a control means for concurrently maintaining the first and second regulator valves in either their first positions or in their second positions.

3. A circuit as in claim 2, said control means including:

a source of piloting fluid,

a first jack and a first return member which are coupled to the movable member of the first regulator valve, the first jack being connected by a first piloting pipe to the source of piloting fluid and having an effect upon the said movable member, which is opposed to that of the first return member, this latter effect returning the said movable member towards the second position of the first regulator valve,

a second jack and a second return member which are coupled to the movable member of the second regulator valve, the second jack being connected by a second piloting pipe to the source of piloting fluid and having an effect upon the said movable member, which is opposed to that of the second return member, this latter effect returning the said movable member towards the second position of the second regulator valve, third regulator valve means having first and second selective positions for connecting said first and second piloting pipes to said source of piloting fluid when in its first position and for connecting said first and second piloting pipes to vent to said fluid tank when in said second position.

4. A circuit as in claim 3, including a third calibrated calibrated valve, the source of piloting fluid comprises valve arranged in the delivery pipe downstream of the the portion of the delivery pipe lying between the second calibrated valve and of the connection to the by-pass pipe, which is itself located downstream of the said second calibrated valve with respect to the first 5 ond calibrated valve and said third calibrated valve. 

1. A hydraulic circuit for the control of a winch by fluid under pressure, including an unwinding position, comprising: a fluid motor having an inlet chamber and an exhaust chamber for the fluid, a source of fluid under pressure, a fluid tank, a feed-pipe connecting the source of fluid to the inlet chamber, a delivery pipe having an upstream end connected to the exhaust chamber and a downstream end communicating with the fluid tank, a first calibrated discharge valve which is arranged in the delivery pipe, a connecting tie-pipe which is connected on one end to the delivery pipe downstream of the first calibrated discharge valve with respect to the motor and is connected on an opposite end to the feed pipe, a flow constriction member for adjustment of the flow of fluid in the tie-pipe, and a second calibrated discharge valve arranged in the delivery pipe downstream of the connection of the tie-pipe to the delivery pipe.
 2. A circuit as in claim 1, including: a by-pass pipe by-passing the first and second calibrated valves, which by-pass pipe has one end connected to the delivery pipe at a location between the motor and the first calibrated valve and which has its other end connected to the delivery pipe at a location downstream of the second calibrated valve with respect to the first calibrated valve, a first regulator valve having at least two positions, which is mounted in the by-pass pipe and which in its first position blocks the by-pass pipe and in its second position ensures the continuity of the said by-pass pipe, a second regulator valve having at least two positions, which is arranged in the connecting tie-pipe and which in its first position ensures the continuity of the connecting tie-pipe and in its second position blocks the said tie-pipe, and a control means for concurrently maintaining the first and second regulator valves in either their first positions or in their second positions.
 3. A circuit as in claim 2, said control means including: a source of piloting fluid, a first jack and a first return member which are coupled to the movable member of the first regulator valve, the first jack being connected by a first piLoting pipe to the source of piloting fluid and having an effect upon the said movable member, which is opposed to that of the first return member, this latter effect returning the said movable member towards the second position of the first regulator valve, a second jack and a second return member which are coupled to the movable member of the second regulator valve, the second jack being connected by a second piloting pipe to the source of piloting fluid and having an effect upon the said movable member, which is opposed to that of the second return member, this latter effect returning the said movable member towards the second position of the second regulator valve, third regulator valve means having first and second selective positions for connecting said first and second piloting pipes to said source of piloting fluid when in its first position and for connecting said first and second piloting pipes to vent to said fluid tank when in said second position.
 4. A circuit as in claim 3, including a third calibrated valve arranged in the delivery pipe downstream of the second calibrated valve and of the connection to the by-pass pipe, which is itself located downstream of the said second calibrated valve with respect to the first calibrated valve, the source of piloting fluid comprises the portion of the delivery pipe lying between the second calibrated valve and said third calibrated valve. 